Abstract
(1) Myocardial hypoxia in the left ventricle exists at rest in the most cases of cor pulmonale, which is not due to decrease in arterial O2 saturation.
(2) In some cases of cor pulmonale, myocardial hypoxia in the left ventricle develop because of the disturbance of coronary circulation during exercise.
(3) Residual blood volume and residual ratio of left ventricle tended to increase in cases of cor pulmonale.
(4) From the foregoing facts, it can be said that the case of cor pulmonale is in the latent phase of left heart failure.
